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Nanoparticles can help solve crimes

Maybe you’ve heard of DNA tests being used to help solve crimes. A few flakes of skin or a hair found at the scene of a crime can be used by scientists to make a kind of genetic fingerprint that can help identify whether a particular person was the criminal or not. This is because our DNA is very unique — so unique that no one else will have DNA that is quite like yours. Scientists use a special method called PCR, or polymerase chain reaction, to take the DNA from a very small sample like a hair and make lots and lots of copies of it — which makes the DNA easier to look at and analyze. It turns out that very tiny particles of gold can help this PCR process work a lot better, and generate even more copies from the original amount of DNA. This means that gold nanoparticles could be considered the world’s smallest crimefighters! Source: